Smelting ores.



PATENTED DEC. 15, 1903.

J. W. MACDONALD- SMELTING ORES. APPLICATION FILED MAR. an, 903.

m) MODEL.

To ail whom it may concern: 1

of Pittsburg, State of Pennsylvania, have invented newalrd useful Improvements in Processes ofSmelti'ng UNITE STAT S PATENT Patented December 15, 1908 7 O FICE.

JOHN W. MACDONALD, 0F PITTSB use, PENNSYLVANIA, ASSIGNOR TO UNITED STATES SULPHIDE'SM-ELTING FURNACE COMPANY, I

OF TOLEDO, OHIO.

- sm me ones.

mmmm forming part of Letters Potent no;

74c,o7o,'dated December 15,1903,

. hpplinetian filedhiaroh 30,1903. sessile. 160,253. (N specime Be it, known that I, JOHN W. MACDONALD,

in the cou uty of Allegheny and 'Qres; and I do hereby declare .the' following to be a full, clear, and exact description of said invention, reference being had to theaccempanying drawings,eand to the figures of refer-.

ence marked thereon, this specification.

My improvements relate more particularly. to the smelting of sulfid ores carrying copper,

which form a part of gold,and situegand consistina method-where in 'unroasted ore is down ,with the aidof ahighly-heatedlair v blast and the gases given on by the'ere, together with'a ceous fnelorwithout extraneous fuel, according as the ore treated-be high or low lindesired gaseous qualities.

mentizl Work of Hollway in the field to which-1 ,1 am fa.mili'ar with the invaluable Iexperi the improvement herein I described particu larly appe'rtain's aswell as with'theapparatus attempts and methods of others of later. date used in largely upon the'd'ata secured byHo llwayY The -,failure heretofore to develop such a etho of smelting sulfid oresinto a commer daily-successful practice would seem to be mu? because ofthe want of knowledge of the" .iu'ietall urgy involved, but rather becauseof thefailure to employ 'such mechanical methods aswou'ld utilize to thevery fullest degree' the well-known valuable forcesto befound in 'ore's'of this class, a conclusion supportedby. operations now being successfully conducted 40 art of on a com mercial scale wherein is being practiced my method herein described.-

, It isw'ell known tothose familiar with the -of the; ordinary smelting-furnace is utilized in operations preliminary to actually"fflfiiDg -1 v 4 k that a large part or. the cost of smelting the press-ordinarily conjednctedenters i-n'fto 'that'ofmoestingrorgcalcin mgit.- QAS the-preliminary.roasting-or cal-- cining of theor'e isnot requ'ired in operations down the ore charge and under this method,"no burden of-ore,

charged l ir ectly int'oa fus--- n g zone of .heat' within afurnace and isfused j small percentage of carbonsto obtain practical resultsbasedmelting sulfid ores that a large'part,

as gemorally understood, i's'cari'ied in the furnace and none is desired, because-to permit the 7 presence of a body oto're above-the fusing zoueof flame would betodesulfn'rize the ore, and thus destroy a valuable *elemeutisoughti tobe-utiliz'edin-the practice of this method, and, further, "as it is desiredftg get the 'full benefit of an the heat'in the furnace above the fusing zone for. the purpose of heating the v lair supplied to the. furnace any ob'struction .abovelthatpoingfsuoh as would be a burden.

would'tendt'o'coolthe escaping gases of lore,

audrenderthem' inefiicient-in heating the airblast. ,Therefore ajfurnace with a hearth of .65

fifty inches necdi o t bejover sixty inches high above the hearthsnd is preferably built cyv lindrical in form, and in the accompanying drawingsuch a f-urh'ac'eisshown not in full detail, rhut (sufficiently so to illustratethis -7o method: -A heating-chamber of the. design 'showngin ;United States Patent No. 720,257

is, erected; adjacent; the furnace for heating 1 ithe air-"lilastvandf isbrought a proper heat preliminary to'charging To: put my-method into operatiomthe fur- 1 thefurnnoejwith bro; '7 5 nace ispreliminarilychargedwith a mixture of unroastedore and' carbouaceouatuelsuifieient-onlyin quantitytoformaconiealbody 1 and just'coveringthe fnrnaee hearth, and'as 18o tw'yers-are of such inclination and proximity-- ;to 'the furnace i-hearth that the"; heated; 'air forced through them under the influence of {the blastimpinges uponthecon icsl body of ore vand carbonaceous fuel 'at-msnypointsgs about its base, which ore soo'nbecomes highly incandescent with resulting copious how of gases. as wellfrom its ore asfromfits-car bonaceous'fnel, and these gases, coming in contact withthe-largevol-ume of heated-o ly ce gen entering the furnace with the blast at many points near its hearth, unite therewith to form Ia body of flame, which completely envelope the conical-formed body,upon the furnace-hearth.

The successful operation of this method contemplatesthe air supplied the furnace reaching the t'vvyers ata temperature approximately'600 Fahrenheit, and because of this high heat the oxygen yielded up by the blast as it enters the furnace unites so rapidly with the gases coming 06 the incandescent ore that the several zones of resulting flame form so close to the points where the blast enters the furnace that the fusing zone of the flame has its base very close to'the furnace-hearth, and as the blast enters at many points around the hearth-thebase of the fusing zone circles that of the incandescent conical body of ore and, rising about said ore-body, forms a mantle 3 of intense heat, which wholly envelops it, and if the conditions herein described, and

consequent upon which this zone of intense heat has been created, are maintained the said fusing zone of flame will always assume and retain the-configuration of the conical ibodypof ore' upon the furnace-hearth and within which zone ofheat the operation of fusing down the 'ore to a liquid mass will take place.

Whi'le Hollways work demonstrated that ,with proper methods it would'be possible to fuse uni-casted sulfid ores without extraneous fuel, his workvery clearly demonstrated the impracticability of accomplishing this result in any manner in which the ore would be ex- :posed to-rapid oxidation before fusion, which conclusion'has been confirmed by later experimenters, notably when it has been attempted'to carry on such fusion in furnaces in which reduction, fusion, and conversion take place,'not'designedly so, but necessarily so, to a more or less extent.

As this method is designedto operate only upon .ores ofacharacter suited to it and performsbut one step in recovering the metal from. such ore-namely, fusing down the ore to a' liquidmass from which the metal compounds may be readily recovered by gravity for subsequent'further treatment, and to bring about this fusion without material preliminary oxidation of the ore operated upon,

and while this ore is in a furnace filled largely with an oxidizingflamereasonable care is required to be exercised to charge the furnace with small quantities of ore at short interwas, to the end that the ore-body upon the furnace-hearth may retain the conical form herein described and that the flow of air entering the furnace be,.sojregulated as that.

the fusing zone of flame'w ill.al'w'aysfbe of such volume as to completely envelop the ore-bodyl v i As is well known in creating a fusing zone of flame in the manner here described, an oxidizing-flame. is also produced which will form the enveloping-mantle 4 of the"fusing zone; but as the movement of this oxidizing zone of flame is in a direction awayfrom the ore upon the furnace-hearth the ore will, so long as such a zone is maintained above the ore, be free from attack by the oxidizingflame, and thus the operation of fusion will go on without material oxidation'that would result in elimination of the non-volatile sulfur, and if an ore be sufliciently high in sulfids and be otherwise suitable to be handled by this method operations may be continued indefinitely without the use of extraneous fuel by successively charging unroastcd ore directly into the fuzing zone of flame at short intervals and in such quantities as may be required to maintain the form and propontions of the ore-bod y upon the furnace-hearth as the ore charge is fused down to a liquid mass, and by supplying such a volume of heated oxygen'to the furnace as that when the same combines with the gases given off by said ore charge such a flame of heat will be created as will form a fusing zone of sufficient volume to wholly envelop the ore to be fused down. Having now described my invention, I claim-- 1. The process of smelting sulfid ores,which consists in placing an initial charge of the raw sulfid ore on a hearth, the inclined sides vcomprising the upper surface of the charge being exposed, heating the charge to a temperature sufficient to enable a portion of the sulfurtherein to combine with oxygen, forcing air upon the exposed inclined sides of the surface of the charge, thereby effecting combustion of a portion of the sulfur and enveloping the charge in a mantle of flame and fusing the outer portions of the charge, and feeding successive portions of raw ore upon the surface of the charge to maintain the charge constantly in the form having inclined sides to receive the air upon its surface, anddrawing off the molten product, as required.

2'. The process of smelting sulfid ores,which consists in placing an initial charge of the raw sulfid ore on a hearth, the inclined sides comprising the upper surface of the charge being exposed, heating the charge to a temperature sufficient to enable a portion of the sulfur therein to combine withoxygen, causing several streams of air to impinge upon the upper surface of the base of the charge and thence rise along its exposed surface, thereby eflecting combustion of a portion of the sulfur and enveloping the charge in a mantleof flame and fusing the outer portions of the charge, and feeding successive portions of raw ore upon the surface of the charge and drawing ofi, the molten product, as required.- t -V.

, 3. The processof smelting sulfid or eswhich consists in placing a conical heap of the raw sulfid ore on a hearth, with its inclined sides exposed, heatingzthe heap to a temperature suficient to enable a portion of the sulfur th'ere into eombine with oxygen, forcing air 'upon the exposed sides of th heap,.thereby efieoting eombustion of a per ion of the s llfu and enveloniiig the heap in .flr mantle of flame and fusing the outer portion 'of the sulfid ore on a hearth; with it's-inclined sides 4. The processof smelting su'lfid 0res,whieh consists in placing. a conical heap of the raw I "exposed; heating-the heap to a. temperature 'suffieientto enables portion of'th'e' sulfur therein-to combine with oxygen, causing sew ez' al streams of 'hotair to-inipinge upon the base of the heap and thence rise along its exposed surface, thereby effecting combos tion of a portion of the sulfur and enveloping the heap in a mantle of flame and fusing the outer portion of the heap, and feeding successive portions of raw ore upon the surfaceof the heap and drawing 01? the molten product, as required.

lmtestimony whereof I affix my signature in presence of two witnesses. v

I JOHN W. MACDONALD.

Witnesses: i H. JOSEPHDOYLE,

' FRANK D. BLACKISTONE. 

